The destruction at Cupola House, home to Strada restaurant, in The Traverse, Bury St Edmunds, caused by fire. Picture taken on 18/06/12 from an aerial ladder.

Flames tore through historic Cupola House, in the Traverse, Bury St Edmunds after a fire – started in the basement kitchen of the Strada restaurant – spread through the Grade 1 Listed building’s ventilation system.

Workers, who are currently removing heat and smoke damaged material from the seat of the blaze, said the cover of the well was discovered after a vinyl floor covering was removed.

David Clarke, project engineer with Richard Jackson Ltd, said: “It is certainly something we have never discovered before. No one we have spoken to that have been advising us during this rebuilding process had told us about it, so it was completely unexpected.”

Mr Clarke said they only realised what they had found in the cellar when they lowered a lamp through the hatch.

The well, which is 9 metres deep and 12 metres below street level, is said to be structurally sound but does not contain any water.

He added: “We removed some slurry from the bottom but there was no water

“Due to abstraction of water in Bury over many years, the water table is now below the bottom of the well.”

The future of the well, like the rest of the building, is now under discussion.

Much of the building, apart from the distinctive frontage, will be pulled down to allow renovation work to continue.

Mr Clarke said: “The well is not in the way at the moment, we can work round it. I hope it will be retained, given that it’s not causing a particular problem.”

He added that it is possible that the well, which is cut into chalk, could be turned into a glass-topped feature to allow people look down it.

But Mr Clarke said the position of the well in the cellar would mean it probably would not be accessed by members of the public.

The well, which pre-dates the construction of the five-storey Cupola House in 1693, will now be researched and hopefully dated by the Suffolk Archaeological Service.

The East Anglian Daily Times previously reported that an investigation by Suffolk Fire and Rescue service had concluded that the fire “started accidentally in the basement kitchen of the building and then spread to the rest of the building initially via the kitchen ventilation system.”

A spokesman added: “The exact fault that led to the fire is still being investigated by the various insurance companies involved, however we know that it started on, in or around the main oven.”